<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <form accept="multipart/form-data" method="POST" action="http://localhost:8081/login2">
        <input type="text" name="userName" value="fanjiantao" />
        <input type="checkbox" name="val[]" value="a">
        <input type="checkbox" name="val[]" value="b">
        <button type="submit">submit</button>
    </form>
</body>

</html>